1. Field of Invention
The present invention relates to a drip irrigation system, and more particularly to a self-discharging drip irrigation system which can eliminate the energy consumption while being cost effective.
2. Description of Related Arts
Drip irrigation is recognized as an advanced technology in the field of irrigation methodology for various cultivation. The advantages of the drip irrigation are that can minimize the water consumption, reduce energy and labor costs, irrigate plant more frequent, so as to increase the quantity and quality of crop production, improve soil aeration, reduces risk of drainage and salinity problems, water can be applied more uniform in the root zone, nutrition can be used more efficient through the system and control weed growth.
During the last four decades an extremely large numbers of drippers, emitters, bubblers, micro-jets, micro-sprayers, etc. have been designed, manufactured, and used to irrigate orchards, vegetables, row crops, nurseries and green houses. Reviewing the development of drip irrigation technology shows a reasonable improvement in practicing drip irrigation methodology. However unfortunately, not any appreciable effort has been made to review, or reconsider the economical feasibility in the field of drip irrigation system.
A conventional drip irrigation system comprises a supply line operatively extended from a water source, at least a feeding pipe having a drip irrigation hose extended from a manifold for distributing the water to a cultivating area, and at least a valve for controlling a flow of water through the connecting pipe.
To operate a conventional drip irrigation system the water has to be transported from the water source to the cultivating area, by applying a predetermined pressure, and the pressure must be applied by the water pump to pump the water through the supply and feeding lines. Practically, the average pressure required to properly operate the conventional drip irrigation system is in the range of 45 to 70 psi (3 to 5 atmospheres), and the average demanding power is in the range of 0.5.0 to 1.0 horse-power per hectare. Accordingly, the supply pipe, main line, sub-main, lateral, and manifold must be strong enough to operate under such high pressure. The conventional drip irrigation system, also requires a filtration unit as well a power plant to operate the system.
In the other hand, the applied pressure must be dissipated through a complicated pressure compensating emitters or drip tubes to control the steady flow rate of water and to provide a reasonable distribution uniformity of water. So, the initial investment costs of the conventional drip irrigation system will be extremely high including the installation cost and maintenance cost. Besides, the energy consumption of the conventional drip irrigation system is relatively high so as to increase the operational costs of the system.
Consequently, with regards to the foregoing disadvantages, practicing of a conventional drip irrigation system, economically is not feasible to be used by most low income farmers, so it is only applicable and affordable for growers of high value crops.
As a result, the growers tend to refuse to use the conventional drip irrigation system which causes the slow development of drip irrigation system especially in undeveloped countries.
Accordingly, The FAO statistical claimed and census 1998 of the United State Department of Agriculture (USDA) of drip irrigation development show that less than one percent (1%) of irrigated lands in the world; 4.2% of irrigated farms, and 8.6% of horticultural land in the United States are pr0acticing drip irrigation methodology.
The foregoing record is a good index that shows drawbacks of the conventional drip irrigation technology, after a half century of practicing this methodology. It is well known by those experts in agricultural economy, that the most problems involved in slow development of drip irrigation system arise from high investment and operational costs
Therefore, it is necessary to review and reconsider the economical feasibility of drip irrigation system and introduce a simplified and new technology to overcome disadvantages of the conventional drip irrigation system.
A main object of the present invention is to provide a self-discharging drip irrigation system, which can reduce the energy consumption while being coast effective.
Another object of the present invention is to provide a self-discharging drip irrigation system, which is capable of transporting a predefined flow of water from a water supply or reservoir to a cultivating area under gravity potential.
Another object of the present invention is to provide a self-discharging drip irrigation system for eliminating costly pumping plant and annual energy costs, which are essential to operate the conventional drip irrigation system.
Another object of the present invention is to provide a self-discharging drip irrigation system which is adapted to eliminate filtration unit and reduces investment and maintenance costs.
Another object of the present invention is to provide a self-discharging drip irrigation system that drips at high emission uniformity (EU) over a wide range of hydraulic head or gravity potential.
Another object of the present invention is to provide a self-discharging drip irrigation system which is simple to install and easy to use.
Another object of the present invention is to provide a simple, inexpensive and easy manufactured self-discharging drip irrigation system to be affordable for low-income farmers and low educated growers in all other countries.
Another object of the present invention is to provide a self-discharging drip irrigation system which is reliable to eliminate clogging and plugging of the system by dirt and debris.
Another object of the present invention is to provide a self-discharging drip irrigation system that can operate in boat surface and subsurface installation.
Another object of the present invention is to provide a self-discharging drip irrigation system to accelerate the development of this art in the United States and in the other countries.
Accordingly, in order to accomplish the above objects, the present invention provides a self-discharging drip irrigation system to solve the technological and economical problems involved in the field of conventional drip irrigation systems.
The self-discharging drip irrigation system is directed to an elongated drip irrigation hose having a transiting waterway for operatively extending from a water reservoir and at least an external emitter having a flow regulating passage extended from the drip irrigation hose, wherein the flow regulating passage has a laminar flow region, wherein a cross-sectional area of the laminar flow region is smaller than that of the transiting waterway. The emitter can be non-pressure compensating emitter to save the pressure applied and to eliminate sedimentation of debris through the emitter.
The emitter has at least one inlet section connected to the drip irrigation hose for communicating the flow regulating passage with the transiting waterway, at least one outlet section for dripping the water to a cultivating area, and at least one laminar flow region defined between the inlet section and the outlet section. The emitter further may comprises at least one venturi accelerator mounted between the inlet section and the outlet section for accelerating the water flow from the inlet section to the outlet section.
In operation, the water flows from a water reservoir through a conventional supply pipe to the drip irrigation hose by gravity potential. Then, the water enters the emitter from the inlet section thereof and exits at the outlet section to the cultivating area to water plants. It is obvious by one expert in fluid mechanics, wherein the gravity potential is attainable in all irrigated farms and dry lands. However, the self-discharging drip irrigation system of the present invention is capable of operating over a wide range of hydraulic head incorporated with a water pump or any other hydraulic pressurized device